Running configure on s390 fails with:
checking whether the C compiler works... no
configure: error: in `/jdk-hs':
configure: error: C compiler cannot create executables

Caused by:
configure:35266: checking whether the C compiler works
configure:35288: /usr/bin/gcc -m32 -m32 conftest.c >&5
gcc: error: unrecognized command line option '-m32'
gcc: error: unrecognized command line option '-m32'
configure:35292: $? = 1
configure:35330: result: no
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME "OpenJDK"
| #define PACKAGE_TARNAME "openjdk"
| #define PACKAGE_VERSION "jdk9"
| #define PACKAGE_STRING "OpenJDK jdk9"
| #define PACKAGE_BUGREPORT "build-dev at openjdk.java.net"
| #define PACKAGE_URL "http://openjdk.java.net"
| /* end confdefs.h. */
|
| int
| main ()
| {
|
| ;
| return 0;
| }
configure:35335: error: in `/jdk-hs':
configure:35337: error: C compiler cannot create executables

Indeed:
<mock-chroot> sh-4.2# gcc -m32 conftest.c
gcc: error: unrecognized command line option ‘-m32’
<mock-chroot> sh-4.2# echo $?
1
<mock-chroot> sh-4.2# gcc conftest.c
<mock-chroot> sh-4.2# echo $?
0

So the compiler test adds the -m32 flag, which isn't supported on that platform.

See also:
http://mail.openjdk.java.net/pipermail/build-dev/2018-April/021676.html